ABSTRACT
The building process includes planning, design, construction, operation/use, and demolition. All components of the process involve uncertainties. These uncertainties can be put into two major categories with regard to causes: human and natural. Human causes include intended and unintended departures from optimum realization. In the design, this can be due to approximation, calculation error, communication problem, omission, lack of knowledge, and so on. Similarly, in the construction, uncertainties are due to use of inadequate materials, inappropriate methods of construction, bad connections, or changes without analysis. During operation/use, the structure can be subjected to overloading, inadequate maintenance, misuse, or even an act of sabotage. Natural causes of uncertainty result from unpredictability of loads such as wind, earthquake, snow, ice, water pressure, or live load, and also material properties, which vary from sample to sample and within the sample. This chapter presents reliability analysis that quantifies the uncertainties by means of a reliability index. The basic reliability theory, employed in the analysis, is presented in Appendix L.
